The instant invention is related to a conveyor system and a scraper therefore. More specifically, the present invention is related to an improved method for mounting and adjusting the tension of a scraper for a conveyor system.
Conveyor systems comprising a continuous belt are well known and used in many industries wherein movement of material over a distance is desired. A particularly important use is the movement of large quantities of material; such as dirt, ore, coal and minerals; from a mine to a transport system such as a truck or railcar outside of the mine. Another important application is the movement of materials to a hopper or storage unit. In many cases the continuous belt, which is typically many meters and can be many kilometers in length, comprises some form of rubber or reinforced rubber and particulates tend to adhere to the rubber. It is therefore very common to have a scraper in contact with the underside of the belt typically, immediately after the point of discharge.
An exemplary conveyor belt scraping or cleaning device is described in WO 2015/134348, by the same inventor. Though there are many variations, the necessary components of a conveyor cleaning device includes a frame for mounting to a structural element of the conveyor assembly and a scraper which is in contact with the belt. Though simplistic in general principle the implementation of a conveyor belt scraper or cleaner is very difficult as the pressure applied to the belt, by the scraper, is of utmost importance and achieving the proper pressure is the subject of much research and design alterations. If the pressure is insufficient the scraper fails to adequately remove particles adhered to the belt. If the pressure is excessive the belt can wear prematurely, the belt tends to overheat which may make the belt softer and therefore more susceptible to adhesion of particles and the belt may actually fail catastrophically which has obvious undesirable ramifications.
A conventional adjustment system for a conveyor belt cleaning or scraping system is illustrated in schematic view, and will be described with reference to, FIG. 1. In FIG. 1, a conveyor belt, 10, generally moving in the direction of arrow, 12, is engaged with a pulley, 14, which may be a drive pulley, thereby passing over a scraper assembly comprising a scraper, 16, wherein the scraper is engaged with the bottom of the conveyor belt. As would be realized, material being transported, 18, is carried on the conveyor and is discharged as the conveyor partially circumnavigates a portion of the pulley and returns for subsequent loading of material wherein the path of the conveyor belt repeatedly traverses a fixed path referred to herein as a track. The scraper is attached to, or integral to, a frame, 20, which may be quite complex including spring mechanisms and the like with further discussions thereof being unnecessary here. The frame, 20, is translationally attached to a bracket, 22, preferably mounted on a fixed structural element, 24, such as a structural component of the conveyor system. A threaded member, 26, is received by a mating threaded hole in the frame and therefore the height of the frame and scraper can be altered by rotation of the threaded member as would be readily understood to those of skill in the art. There are certain advantages to the conventional adjustment mechanism, as illustrated schematically in FIG. 1, including fine control of the height of the scraper and therefore the pressure and ease of operation and therefore this type of adjustment system has been the predominant system of choice.
There are problems with the conventional adjustment mechanism represented by FIG. 1 one of which is realized when routine maintenance is necessary. It is not uncommon for scrapers to become damaged, worn or dislodged thereby requiring the frame to be moved away from the conveyor belt to disengage the scraper from the conveyor belt for repair. Once the repair is complete the frame is moved towards the conveyor belt to reengage the scraper. Achieving the proper pressure on the belt is a difficult task and each time the scraper engagement is altered adjustment is required. This is a major source of maintenance cost for conveyor operators and owners and the impact of improper pressure can be devastating. Furthermore, the adjustment is subject to the judgement of the operator which leads to inconsistencies.
There is an ongoing, and long felt, desire for a mechanism of adjustment for a conveyor belt scraper or cleaner which is less susceptible to degradation by materials and which can allow for rapid, and repeatable adjustment after routine repairs. Such a system is provided herein.